Perfluoroalkanesulphonamides

ABSTRACT

PERFLUOROALKANESULPHONAMIDES OF THE FORMULA   RF-(CH2-CH2)M-SO2-N(-R1)-(A-N(-SO2-(CH2-CH2)M-RF))(N-1)-A-   N(-R2)-SO2-(CH2-CH2)M-RF   IN WHICH RF, A, R1, R2, N AND M HAVE THE MEANING GIVEN IN THE DISCLOSURE BELOW, A PROCESS FOR THEIR MANUFACTURE AND THEIR USE AS OLEOPHOBIC AGENTS.

United States Patent ()flice 3,829,466 Patented Aug. 13, 1974 3,829,466 PERFLUOROALKANESULPHONAMIDES Adolf Staffe, Opladen, and Klaus Gerlach, Cologne, Germany, assignors to Bayer Aktiengesellschaft, Leverkusen, Germany No Drawing. Filed Oct. 26, 1972, Ser. No. 300,892 Claims priority, application Germany, Oct. 26, 1971, P 21 53 270.7 Int. Cl. C07c 143/74 US. Cl. 260-481 R 21 Claims closure below, a process for their manufacture and their use as oleophobic agents.

The invention relates to perfluoroalkanesulphonamides; more particularly it concerns perfluoroalkanesulphonamides of the formula in which R; represents a perfluoroinated alkyl radical, preferably a perfluorobutyl radical,

A denotes an alkylene group which is optionally interrupted by oxygen or sulphur atoms,

R and R independently of one another represent hydrogen or an optionally substituted alkyl group,

n represents a number from 1 to 4 and m is l or preferably 0,

a process for their manufacture, and their use as oleophobic agents.

For R perfluoroalkyl radicals to be mentioned are especially c -C -perfluoroalkyl radicals, for example the H-C3F7-, n-C F lJ-C F n-c -F1q-, iSO-CgFrr', H'C10F21', isO-C F and I1-C12F25- radical.

Possible alkylene groups A are above all alkylene radicals with 2 to 10, preferably 2 or 3, C atoms, for example the --CH CH As examples of optionally substituted alkyl groups which R and R can be, there may be mentioned: lower alkyl radicals, for example C -C -alkyl radicals, such as the methyl, ethyl, n-propyl, n-butyl and sec.-butyl radical and substituted C C -alkyl radicals, for example C -C alkyl radicals substituted by hydroxyl, lower alkoxy, nitrile or C C -acyloxy groups, such as the to the invention, of the formula I, the following compounds are particularly preferred:

(A) The perfluoroalkanesulphonamides of the formula I,

if, in this, R represents hydrogen and R represents hydrogen or another alkyl group.

(B) The perfluoroalkanesulphonamides of the formula I, if, in this, R and R independently of one another represent an optionally substituted alkyl group.

The compounds according to the invention are obtained by reaction of amines of the formula HN(A-NH) ..-1A-N-H in (II) in which A and n have the meaning indicated under formula I and R and R independently of one another represent hydrogen or a lower alkyl group,

with perfluoroalkanesulphonyl halides of the formula R,-(CH CH -SO X (III) in which X represents chlorine or preferably fluorine and R, and m have the meaning indicated under the formula I.

The reaction is carried out at temperatures of 0 to 150 0, preferably 40 to C., in the presence of acidbinding agents, such as inorganic bases, for eXample, potassium carbonate, or organic bases, for example tertiary amines, such as triethylamine or pyridine or alcoholates, such as sodium methylate, optionally in organic solvents which are inert under the reaction conditions. The molar ratio of the polyamine of the formula (II) which is to be reacted and of the perfluoroalkanesulphonyl halide (III) is so chosen that about one mol of sulphonyl halide is present per mol of amino group to be reacted.

In order to manufacture the perfluoroalkanesulphonamides of the formula I in which R, and/or R represent a substituted alkyl group, the perfluoroalkanesulphonamides obtained in the reaction are alkylated in a manner which is in itself known with substituted alkyl compounds, for example alkyl compounds substituted by hydroxyl, lower alkoxy or acyloxy groups, such as chlorohydrin, epichlorohydrin, glycol carbonates or fi-acetoxyethyl chloride, fl-propionyloxyethyl chloride, fl-acryloyloxyethyl chloride, or B-methacryloyloxyethyl chloride.

The perfluoroalkanesulphonamides substituted by wacyloxyalkyl groups are also obtainable in a simple manner by acylation of the corresponding perfluoroalkanesulphonamides substituted by w-hydroxyalkyl groups.

As examples of representatives of the compounds according to the invention, of the formula I there may be mentioned:

BIS oily-onion: s 0.11.

CH2 CH2 R! S OzIIICHnCHzCHzIf S 02R! CHgCHnCHrN S 02R RISOaN CHICHZOCO CH=CH1 CH CH3 R; S OzN-CHzCHBCHzOHzCHgCHzN S 02R:

CHZCHQOCOCH=CHZ CH2CH2OCOCH=CH2 ms om-ornomcmoHzcmcHr-N-s 02R:

omomorr omornorr R =C4Fv, Cs u R! S O2NCH2CH2CH1CH2CH2CHZN S 02R! omomoooc=om cmomoooo=cm on. (3H3 The compounds according to the invention, of the formula I, are valuable agents for the oleophobic finishing of materials made of paper, wood, textiles and filaments.

It should be emphasised that an excellent oleophobic effect is achieved not only with the sulphonamides of the formula I which contain perfluorooctyl groups but also with the compounds containing perfluorobutyl groups. This is surprising since the opinion has hitherto prevailed amongst experts (see Textilveredlung 2 [1967], page 463) that for oleophobic agents based on perfiuoroalkylsulphonamides the chain length of the perfiuoroalkyl radical must be 6 to 8 C atoms.

Example 1 604 g. (2 mols) of perfluoro-n-butanesulphonic acid fluoride are added dropwise, at a temperature of 85 C., to a mixture of 60 g. (1 mol) of ethylenediamine and 202 g. (2 mols) of triethylamine at such speed that the temperature of the reaction mixture does not drop below C. To complete the reaction, the reaction mixture is stirred for 5 to 6 hours at C. After distilling off the excess triethylamine, the residue is washed 3 times with 10% strength hydrochloric acid and then with water until the latter reacts neutral.

Th6 disulphonamide C4FQSO3NHCHZCHZNHSO2C4FQ (molecular weight 624) is obtained in the form of a yellowish sandy powder, in a yield of 599 g. ('=96% of theory).

Analysis: F: 54.8 calculated. 54.7 found. N: 4.5 calculated. 4.33 found. S: 10.25 calculated. 10.1 found.

On replacing the ethylenediamine by the equivalent amount of N,N'-dimethylethylenediamine and following the same procedure, the disulphonamide was obtained.

Example 2 604 g. (2 mols) of perfluoro-n-butanesulphonic acid chloride are added dropwise at 89 C. to a mixture of 116 g. (1 mol) of 1,6-diaminohexane, 158 g. (2 mols) of pyridine and g. (1.3 mols) of triethylamine. After stirring for a further 3 hours at 89 C., the reaction mixture is worked up as described in Example 1. The disulphonamide C F SO NH(CH NH,SO C F (molecular weight: 680) is obtained in the form of a light yellowish brown sandy powder in a yield of 591.6 g. ('=87% of theory).

Example 3 906 g. (3 mols) of perfluoro-n-butanesulphonic acid fluoride are added dropwise at 89 C. to a mixture of 103 g. (1 mol) of diethylenetriamine, 505 g. (5 mols) of triethylamine and 7.9 g. of pyridine (0.1 mol). After stirring for a further 5 hours at 89 C., the reaction mixture is worked up as described in Example 1. The trisulphonamide.

(molecular weight: 949) is obtained in the form of a light brownish sandy powder in a yield of 750 g. ('=79% of theory).

Example 4 604 g. (2 mols) of perfiuorom-butanesulphonic acid fluoride are added dropwise at 89 C. to a mixture of 88 g. (1 mol) of 3-amino-1-methylaminopropane and 303 g. (3 mols) of triethylamine. After stirring for a further 3 hours at 89 C., the reaction mixture is worked up as described in Example 1. The disulphonamide (molecular weight: 652) is obtained in the form of a yellowish sandy powder in a yield of 556 g. (=89% of theory).

Example 5 251 g. (0.5 mol) of penfluoro-n-octanesulphonic acid fluoride are slowly added dropwise at 85 C. to a mixture of 15 g. of ethylenediamine (0.25 mol), 202 g. (2 mols) of triethylamine and 39 g. (0.5 mol) of pyridine. After stirring for a further 4 hours at 85 C., the reaction mixture is worked up as described in Example 1. The disulphonamide C F SO NHCH CH NHSO C F (molecular weight: 1024) is obtained in the form of a yellowish sandy powder in a yield of 215 g. =84% of theory).

Example 6 251 (0.5 mol) of perfluoro-n-octanesulphonic acid fluoride are slowly added dropwise at 85 C. to a mixture of 22 g. (0.25 mol) of 3-amino-l-methylaminopropane, 202 g. (2 mols) of triethylamine and 39 g. (0.5 mol) of pyridine. After stirring for a further 8 hours at 85 C. the reaction mixture is worked up as described in Example 1. The disulphonamide (molecular weight: 1052) is obtained in the form of a slightly sticky powder, in a yield of 726 g. =79% of theory).

Example 7 624 1g. (1 mol) of C F SO NHCH CH NHSO C F are dissolved in 800 ml. of absolute methanol. The solution is mixed with 137.5 g. (2.5 mols) of sodium methylate and 162 g. (2 mols) of ethylene-chlorohydrin and the whole is stirred for 3 hours at 67 C. The unreacted ethylene-chlorohydrin is then distilled off under reduced pressure and the residue is stirred for 1 hour with diethyl ether at 35 C. The ether phase is separated oif and washed alternately with water and with 2% strength sodium hydroxide solution. After distilling off the ether, the N,N'-di-alkylated perfluorobutylsulphonamide is left in the form of a yellowish, coarse-grained, sightly smeary solid.

Yield of C4F9SOzN-CH2CH2NSO204F9 CHZCHZOH OHZCHZOH (molecular weight: 712): 619 g. (=87% of theory).

In the same manner, the reaction (a) of 1 mol of the disulphonamide described in Example 4 with 1 mol of ethylene-chlorohydrin gave N- -methyl-N'-(2 hydroxyethyl)-N,N-di-perfluorobutanesulphonyl-ethylenediamine 75.5 g. (0.25 mol) of perfluoro-n-butanesu1phofluoride (b) of 1 mol of the disulphonamide described in Example 6 with 1 mol of ethylene-chlorohydrin gave N-methyl- N- (2 hydroxyethyl) -N,N'-di-perfluorooctanesulphonyl-propylenediamine Example 8:

619 g. (0.87 mol) of C4FaSOzNCHzCHr-NSOiC4 0 CHzCHzOH CHzCHzOH are dissolved in boiling benzene. After adding 5 ml. of concentrated H SO and 130 g. of acrylic acid the reaction mixture is heated to the boil until the water formed during the esterification has quantitatively been distilled off azeotropically. After cooling, the reaction mixture is neutralised with sodium hydroxide solution and filtered. The solvent is distilled from the filtrate under reduced pressure. The diacrylic acid ester is left in the form of a slightly yellowish soapy solid in a yield of 642 g. (=90% of theory).

oimsom CHaCH2-NSOzC4F CHzCHaO-COCH=CH: CH2CHzOCOCH=CHz Example 9 624 g. (1 mol) of C F SO NHCH CH NHS0 C F are dissolved in, 800 ml. of absolute methanol. After adding 115.5 g. (2.1 mols) of sodium methylate, the solution is stirred for 4 hours at 67 C. Thereafter the solvent is distilled off. The residue is treated with 295 g. (2.2 mols) of ClCH CH OCOCH=CH and the mixture is stirred for 9 hours at 90 C. A product which is identical with that described in Example 8 is obtained.

Example 10 125.5 (0.25 mol) of perfluoro n octanesulphofiuoride are slowly added dropwise, at C, to a mixture of 22 g. (0.25 mol) of 3 amino 1 methylaminopropane, 202 g. (2 mols) of triethylamine and 39 g. (0.5 mol) of pyridine. After stirring for a further 3 hours at 85 C.,

are slowly added dropwise at the same temperature. After stirring for a further 6 hours at 85 C., the reaction mixture is Worked up as described in Example 1. The disulphonamide i OBF S 0zN--CHzCH2-CH2N S 02C4F9 is obtained.

Example 11 Cotton is impregnated with a 1% strength solution of the perfluoroalkanesulphonamide described in Exam- 7 ple 7, in acetone, squeezed out to a weight increase of 80% and dried for 10 minutes at 100 C. In the 3 M- test, this fabric (deposit of oleophobic agent: 0.8% by weight) receives a rating of 100.

If instead of the 1% strength solution of the compound described in Example 7 an 0.5% strength solution of the perfluoroalkanesulphonamide described in Example 8 in acetone was used and the fabric (a) was squeezed out to a weight increase of 60% and (b) in another experiment the fabric was squeezed out to a weight increase of 100%, fabrics were obtained which in the 3-M test received the following ratings:

(a) (0.3% deposit) Rating 90 to 100 (b) (0.5% deposit) Rating 100 Additionally, the 1% strength solutions in acetone of the compounds described in Example 7 and 8 were used for impregnating filter paper and timber. The oleophobic effect achieved on these materials was given the rating 120.

The oil-repellent effect of the fabric, paper and timber products described was assessed in accordance with the so called 3M oil repellency test (Crajeck, Petersen, Textile Research Journal 32, pages 320 to 331 (1960)) using heptane-paraffin oil mixtures. In the assessment, 150 denotes the best achievable rating and 50 the worst rating. The various samples were assessed immediately after drying.

What is clamed is:

1. Perfluoroalkanesulphonamide of the formula Rr-(CH1CHz)mSOg-N(AN)n-1 ANSOz-(C 2CH:)m" I R1 sOz-(OH2CH2)m-Rl 3 in which R; is C -C -penfluorinated alkyl;

A is C -C -alkylene; C -C -alkylene interrupted by oxygen; or C -C -alkylene interrupted by sulphur;

R and R independently of one another are hydrogen;

C -C -alkyl; or C C -alky1 substituted by hydroxyl, lower alkoxy, nitrile or alkyl carbonyl oxy or alkenyl carbonyl oxy having 1 to 6 carbon atoms;

n is a number from 1 to 4; and

m is or 1.

2. Perfluoroalkanesulphonamide of Claim 1, in which R is hydrogen; and R is hydrogen or C C -alkyl.

3. Perfluoroalkanesulphonamide of Claim 1, in which R and R independently of one another are C -C -alkyl substituted by hydroxyl, lower alkoxy, nitrile, or alkyl carbonyl oxy or alkenyl'carbonyl oxy having 1 to 6 carbon atoms.

4. Perfluoroalkanesulphonamide of Claim 1 in which R, is perfluorobutyl; and m is 0.

5. Perfluoroalkanesulphonamide of Claim 1 in which R, is perfluorobutyl; m is 0; and A is c -C -alkylene.

6. Perfluoroalkanesulphonamide of Claim 1 selected from the group consisting of R SOzNHCHgCHzNHSOgRf R C4Fn or CUFF];

CHgCHzCHzNSOzRl 

